Patch :
Some users had errors randomly. They should now be fixed (nevertheless if you continue to see them in your console, do not hesitate to contact me).

Notes :
The 1.13 seems to have changed the system of pluginmessages used by HackedServer, so it will be difficult to maintain compatibility with older versions while supporting 1.13. I will try to rewrite my own system to no longer depend on spigot.